Statement of Objectives
Advantages of wire-arc spray system, including its low costs and high material/energy
efficiency, have made its market grow rapidly in the thermal spray industry. Despite its simple
design, the physical phenomena underlying its operation are very complex and have yet to be
understood. Fundamental understanding of the wire-arc spray process is needed to better control
the spray particle properties and optimize its performance for different industrial applications.
Better understanding of the wire-arc spraying process will also provide us with some guidelines
as to how existing wire-arc spray equipment designs can be modified to improve the quality of
the produced protective coating layers.
The objective of this research is to quantitatively analyze and model how the wire
material is heated, melted, atomized, transported, and deposited onto the substrate: Knowledge of
fluid flow in the wire-arc gun is necessary to predict the size and shape of the primary
detachments from the wire-tips. Knowledge of particle properties and their distributions is
needed because it directly affects the quality of the produced coating. Knowledge of individual
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particle deposition (and splat formation) is necessary because it determines the microstructure of
the produced coating layer.
As different industrial applications of thermal sprays require different ranges of particle
velocities, particle temperatures, and particle sizes, the ultimate goal of this research is to use the
obtained knowledge and suggest methods of controlling/enhancing the wire-arc process and
make it more suitable for each application.